Bleaching earth



Patentd ay 22, 1923.

si" as CARL CBAM BQ OF. ZURZACH, SWITZERLAND.

I'IBILEACEING EARTH.

- No Drawing.

.To whom; it may concern: Be it lmown that I, CARL CRAMER, acitizen of the Swiss Republic, and resident Gaze tities of earthy matters having ,bleac ing' properties are used. Such mineral .matters consist inthe main of aluminium hydrosilimites and are found in large quantities invarious places. They. are. known in trade under such names asForida earth, florldin,

fullers earth. Fre uentl however, it is. not y the natural materi which is used,' this material being first subjected to-a relimina 'y treatment. Such treatment is or the purpose of enhancing the bleaching: power of the mineral; it may consist in cautious heating to expel h groscopic Water, or in treating the minera with an acid such as hydrochlo- I iearths having a high bleaching effect by ricor sulfuric acid. Products of this kind are those known as tonsil and frankonit.

In practice, thecrude material .is treated with hydrochloric acid of about 15% strength. This operation known. asopening u generally lasts for two hours, and is roan $0 med out at boiling temperature, that is "to say, by continuous'injectioniof. steam.

According to the present invention, this openin up can be achieved in a surprisingly short time by emulsifying the material with an acid of 1% strength in :the cold. This emulsification or homo eniaing may be :effected for instance wit the .aid of ilmown homogenizing :Pparatus, comprisingrat least one centri'fug wheel as, for-instance, 1a 40 turbomixergcapable'of producing emuilsk ficaition of an .i'ntensit'ysufiicientto enhance notably, .byitself, :the. bleaching A lication iuea Februaryi 27,1t22 .w-Serial ml ssa'm.

power of the aluminium hydrosilicates, even when thelremulsifying would be performed with ewater alone, that lSatO say, without the v .aid of an acid. The product thus prepared is particularly well'o .ened up both chemi-- vcally and. physically as av more powerful bleaching efl'ect'ithan anyiof the known prod- 'ucts. Apart from'thisimportant fact, there' is the great-a,dvantageiin:practice that fuel and the greater part of the acid hitherto used are saved. 4 t y The followingexamplejillustrates the in-. ventionz- 1,000- kilos .of ad aearth ofthe kind in question are'stirred with3,000 litres of hy-. drochloric acidof 1%:strength in a wooden vat. provided with a-stirrer, and are emulsified with the aid-of .the-lknown turbo mixer. After ten minutes the charge is drained, washed with water and then dried in a d ing oven.

'l Vhat I claim is 1. A process for obtaining bleaching treating aluminiumjhydro-silicates with an acid, consisting in mixing the aluminium hydro-silicates with ,dilute hydrochloric acid 1 and emulsifying the resulting mixture intenselg in the cold. g

2. new products, "bleaching-earths having ahigh bleaching efi'ect, the rsaid bleaching earths having been opened up chemically and physically by their emulsificaztion with dilute .hydrochlor iczacid in :the cold, substanltially as set forth. A

In witness whereo'fil have hereunto signed my nazmeithis 'ififlfih'daybf February, 1922, in the presence oftwoisubscribiarg witnesses.

Witnesses: i

Fzmno IK iii magm 

